McLaren chairman Ron Dennis' position is under threat from his fellow shareholders.

Ross Brawn, Justin King and Martin Whitmarsh could replace him.

Insiders say Dennis, who has been in charge for 35 years, is set to leave at the end of the year, but the company is yet to decide who would come in.

But Brawn, the ex-Mercedes F1 boss, King, former head of Sainsbury's, and Whitmarsh, sacked by Dennis as McLaren team principal in 2014, are contenders.

However, it remains to be seen whether any of the three ends up with the job, as it would be an appealing position for senior executives and other names are almost certain to be on the list.

King is attending the US Grand Prix this weekend where he told BBC Sport: "There isn't a vacancy".

Work-life imbalance? Dennis owns 25% of McLaren Group, and has run the team since 1981

McLaren have said in a statement that Dennis is "not stepping down".

But that does not rule out him being replaced at the end of the year, when his contract is believed to run out.

Dennis has run McLaren since 1981 and has made it into one of Formula 1's most successful teams, and now a leading manufacturer of high-end sports cars for the road.

But he has for some time had an uncomfortable relationship with fellow shareholder Mansour Ojjeh - who, like Dennis, owns 25% of the McLaren Group.

The remaining 50% is owned by the Bahraini royal family through their Mumtalakat investment fund.

Ojjeh - seen here with Lewis Hamilton at the Austrian GP in 2015 - owns the same shareholding as Dennis

McLaren's statement added: "[Dennis] remains contracted as chairman and chief executive officer of McLaren Technology Group, and he retains a 25% shareholding in the Group - exactly equal to that of Mansour Ojjeh.

"Over many years, many decades in fact, McLaren shareholders have often entered into dialogue on the subject of potential equity movements and realignments, and Ron and Mansour have always been central to those discussions.

"That is still the case. Their recent conversations can therefore be categorised as 'more of the same'.

"However, it would be inappropriate to reveal further details of such discussions, which are of course private and confidential."